Level shift circuit
US6696877B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 2, 2002 |
| Grant date | Feb 24, 2004 |
| Priority date | — |
| Expiry date | May 2, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F1/30
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
Level shift circuit includes an operational amplifier, and an input resistor having one end connected to an output terminal of an amplifier circuit and the other end connected to the inverted input terminal of the operational amplifier. The level shift circuit further includes a level-shifting resistor of a resistance value R0 having one end connected to the inverted input terminal of the operational amplifier and the other end connected to a ground, and a feedback resistor of a resistance value R1. Reference voltage Vref is applied to the noninverted input terminal of the operational amplifier. Output signal of the level shift circuit represents the output of the amplifier circuit having been shifted in level by a predetermined amount. If the amplitude center level of the output signal from the level shift circuit is represented by Vc, the level shift amount &Dgr;V can be expressed as&Dgr;V=Vc−Vref=(R1/R0)VrefWith such arrangements, the level shift circuit can operate appropriately using only one reference voltage, without requiring any external capacitor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.